Trophic Levels: Feeding levels in a ecosystem

Ecosystem trophic structure

All living things must have enough food to enable them to perform their vital functions. Food provides energy and matter .

As you know, photosynthesis is essential to sustain life on Earth, and heterotrophic beings depend on food production made by autotrophs.

Considering the type of nutrition and the role that organisms play in ecosystems, can be classified into three main groups, called trophic levels : products, consumers and decomposers.

· Producers . They are autotrophic organisms: plants, algae and photosynthetic bacteria. They are named for their ability to synthesize organic matter starting from simple inorganic substances (carbon dioxide, water and minerals). In this process, light energy is stored in the chemical bonds of organic molécules large.

They are also chemosynthetic autotrophic bacteria, but their role as producers of the biosphere is not very important.

· Consumers . Animals are heterotrophic organisms that obtain matter and energy needed directly from producers or other animals that have eaten producers. They can be:

– Primary consumers . They are called vegetarians, feeding on producers.

– secondary consumers . They are carnivores that feed on primary consumers.

– Consumers tertiary, quaternary, and higher level . Those carnivores that feed on other carnivores.

· Decomposers . They are also heterotrophs, as some bacteria and fungi that feed on organic debris: corpses, feces, molts, etc.. In this process food decompose organic matter and transformed into inorganic.

To graph the feeding relationships, uses the food chains . A food chain is made ​​up of organisms belonging to different trophic levels. The arrows indicate the direction in which the transfer and energy meteria, ie the arrow means “is eaten”.

In an ecosystem , the relationships are not as simple as a single body for several pede be eaten and, in turn, also feed on many others. The graphical representation of this process is a net-like pattern, with many connections diferntes food, called food web .